Ludus FastMCP

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'Export' implies a read operation that outputs data, it doesn't specify whether this is a long-running process, requires admin privileges beyond the user_id parameter, has rate limits, or affects system state. The mention of 'admin only' for user_id hints at permission requirements but doesn't fully describe access controls or behavioral traits.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured and appropriately sized. It front-loads the core purpose ('Export metrics data') and follows with organized sections for Args and Returns. Each sentence earns its place by providing essential parameter documentation. However, the core purpose statement is overly brief and could be more informative without sacrificing conciseness.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (4 parameters, no annotations, but has output schema), the description is partially complete. The parameter documentation is thorough, but the purpose and usage guidance are minimal. The output schema existence means the description doesn't need to detail return values, but it should better explain the tool's role versus siblings and its behavioral characteristics to be fully adequate.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description adds significant value beyond the input schema, which has 0% schema description coverage. The Args section explicitly documents all four parameters: format (with allowed values: json, csv, prometheus), start_time and end_time (ISO format), and user_id (admin only). This compensates fully for the schema's lack of descriptions, providing clear semantics and constraints for each parameter.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Export metrics data' is a tautology that merely restates the tool name 'export_metrics'. It specifies the resource ('metrics data') but lacks a specific verb or any distinguishing details about what kind of export this is (e.g., bulk download, real-time stream, report generation). Compared to sibling tools like 'get_range_metrics' or 'get_deployment_metrics', it doesn't clarify how this export differs from those retrieval operations.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With siblings like 'get_range_metrics' and 'get_deployment_metrics' that likely retrieve metrics in different contexts, there's no indication of whether this tool is for administrative bulk exports, historical analysis, or integration purposes. The Args/Returns section lists parameters but doesn't offer usage context or prerequisites.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.